National Guard and Reserve (NGR) families face many unique challenges in meeting the combined demands from their civilian and military contexts. Clearly, the strength and stability of families are crucial to effective and productive service members; healthy family functioning is critical to deployment-related readjustment or reintegration into communities of residence. Child behavioral problems and decreased family functioning, especially during deployment and reintegration, can compromise the strength of military families through youth emotional difficulties, initiation of substance misuse, decreased school achievement, and poorer family communications. The proposed research will apply the scientifically proven PROSPER delivery system for evidence-based, family-focused interventions to achieve the goal of strengthening NGR families-reducing youth problem behaviors and decreasing family dysfunction-by integrating and synergizing civilian and military support infrastructures for military families. The research includes three aims: (1) To adapt modifiable implementation procedures of the civilian evidence-based PROSPER delivery system for NGR families, to address unique challenges and specific features of their lives and culture; (2) To evaluate implementation of the adapted PROSPER implementation in sites where NGR families reside; and (3) To examine PROSPER outcomes with NGR families using a randomized controlled design in 24 sites, with 720 families at baseline. The three project aims include a series of overlapping research activities to address the overarching question of PROSPER potential for addressing a top priority of military leadership concerning NGR families. Aim 1 will be accomplished through focus groups and key informant interviews that address modifiable aspects of the PROSPER implementation. Aim 2 will be achieved by identifying and assessing factors associated with variations in the quality of PROSPER implementation, including the effectiveness of local teams, across 12 intervention sites and to examine relationships between local team processes and the quality of program implementation. Aim 3 will examine intervention outcomes for NGR families (parents and youth). Outcomes will include targeted youth substance misuse and other problem behaviors, family functioning, parent and youth competencies, and parent-youth relationship quality. If the adapted implementation of this evidence-based delivery model proves efficacious, there is a high likelihood that it can be widely implemented with NGR families-and perhaps their active duty counterparts-and have a substantial impact by reducing youth risky behaviors and enhancing family functioning, thereby improving service member readiness, readjustment, and reintegration.